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(1) EN 199115 gives principles and rules for calculating thermal actions on buildings, bridges and other structures including their structural elements. Principles needed for cladding and other appendages of buildings are also provided. (2) This Part describes the changes in the temperature of structural elements. Characteristic values of thermal actions are presented for use in the design of structures which are exposed to daily and seasonal climatic changes. Structures not so exposed may not need to be considered for thermal actions. (3) Structures in which thermal actions are mainly a function of their use (e.g. cooling towers, silos, tanks, warm and cold storage facilities, hot and cold services etc) are treated in Section 7. Chimneys are treated in EN 130841.
BRITISH STANDARD BS EN 1991-1-5:2003 Licensed Copy: na na, University of Northumbria (JISC), Mon Oct 16 03:47:14 BST 2006, Uncontrolled Copy, (c) BSI Incorporating Corrigendum No Eurocode 1: Actions on structures — Part 1-5: General actions — Thermal actions The European Standard EN 1991-1-5:2003 has the status of a British Standard ICS 91.010.30 12 &23[...]... linear temperature difference component (cooling) ∆TE non-linear part of the temperature difference component ∆T sum of linear temperature difference component and non-linear part of the temperature difference component ∆Tp temperature difference between different parts of a structure given by the difference of average temperatures of these parts Latin lower case letters h height of the cross-section... component for other types of bridges 6 .1. 2 Consideration of thermal actions (1) Representative values of thermal actions should be assessed by the uniform temperature component (see 6 .1. 3) and the temperature difference components (see 6 .1. 4) (2) The vertical temperature difference component given in 6 .1. 4 should generally include the non-linear component, see 4(3) Either Approach 1 (see 6 .1. 4 .1) or... (see 6 .1. 4.2) should be used NOTE: The selection of the approach to be used in a Country may be found in its National Annex (3) Where a horizontal temperature difference needs to be considered a linear temperature difference component may be assumed in the absence of other information (see 6 .1. 4.3) 6 .1. 3 Uniform temperature component 6 .1. 3 .1 General (1) The uniform temperature component depends on. .. bridges Top warmer than bottom Bottom warmer than top ∆TM,heat (oC) ∆TM,cool (oC) Type 1: Steel deck 18 13 Type 2: Composite deck 15 18 Type 3: Concrete deck: - concrete box girder - concrete beam - concrete slab 10 15 15 5 8 8 Type of Deck NOTE 1: The values given in the table represent upper bound values of the linearly varying temperature difference component for representative sample of bridge geometries... annex may specify values for linear temperature differences In the absence of detailed information the recommended value is 5oC (2) For walls the linear temperature differences between the inner and outer faces should be taken into account NOTE 1: The National annex may specify values for linear temperature differences In the o absence of detailed information the recommended value is 15 C NOTE 2: When... 1, 0 1, 0 1, 0 1, 0 10 0 0,7 1, 2 1, 0 1, 0 0,7 1, 0 15 0 0,7 1, 2 1, 0 1, 0 0 ,5 1, 0 ballast ( 750 mm) 0,6 1, 4 0,8 1, 2 0,6 1, 0 1) These values represent upper bound values for dark colour 6 .1. 4.2 Vertical temperature components with non-linear effects (Approach 2) (1) The effect of the vertical temperature differences should be considered by including a non-linear temperature difference component (see 6 .1. 2.2) NOTE... 6 .1. 1 Bridge deck types (1) For the purposes of this Part, bridge decks are grouped as follows: Type 1 Steel deck: Type 2 Composite deck Type 3 Concrete deck: - steel box girder - steel truss or plate girder - concrete slab - concrete beam - concrete box girder NOTE 1: See also Figure 6.2 NOTE 2: The National Annex may specify values of the uniform temperature component and the temperature difference... bridge 6 .1. 4.4 Temperature difference components within walls of concrete box girders (1) Care should be exercised in the design of large concrete box girder bridges where significant temperature differences can occur between the inner and outer web walls of such structures NOTE: The National annex may specify numerical values for the temperature difference The recommended value for a linear temperature... Expression (5 .1) should be determined as the average temperature of a structural element in winter or summer using a temperature profile In the case of a sandwich element T is the average temperature of a particular layer NOTE 1: Methods of the thermal transmission theory are indicated in annex D NOTE 2: When elements of one layer are considered and when the environmental conditions on both sides are similar,... cantilever NOTE: Values of the initial temperature difference may be specified in the National Annex 6 .1. 4 .1 Vertical linear component (Approach 1) (1) The effect of vertical temperature differences should be considered by using an equivalent linear temperature difference component (see 6 .1. 2(2))with ∆TM,heat and ∆TM,cool These values should be applied between the top and the bottom of the bridge deck NOTE: